The york 15kg cast iron dumbbell set is a awesome set to put into any home gym great for building the chest arms and back muscles designed to provide comfortable and safe yet very challenging workouts the set consists of 8 x 1 25kg 4 x 0 5kg discs and 4 spinlock collars to prevent them from sliding off the bar during use meaning the possibility of injury or damage to equipment is decreased significantly like all of york s equipment the york 15kg cast iron dumbbell set are reliable du